The city of San Francisco has never seen such doing of derring — or such jubilant solidarity — as on this Friday, Nov. 15, henceforth known as Batkid Day.

Miles Scott, a 5-year-old leukemia patient, was the star of a citywide production put on by the Make-A-Wish Foundation. Wearing an elaborate Batman costume (and Velcro shoes with bright orange straps), the pint-sized superhero rescued a damsel strapped across the city’s cable car lines; he foiled the Riddler mid-bank robbery in the financial district; he tracked the Penguin to the Giants stadium and freed their mascot, Lou Seal, from his finny clutches. And at each stop, thousands of people, many covered in Batman yellow, cheered him on — chanting his name and booing his enemies.

Homemade signs read “Help, Batboy!” and “Thanks, Batkid!” and “Miles, You’re Our Hero.” The mini-masked avenger chased his foes in a decked-out Lamborghini, complete with Batman sigil and police escort. Sirens and helicopters whirled in the background. San Francisco police decorated their motorcycles with signs that said “KAPOW!” and sold out of specially made “Batkid” T-shirts. Passersby honked their horns in support, a 400-person flash mob helped direct Batkid to the Penguin’s whereabouts, and people cried.

Supporters who traveled from Sacramento for the event said the best part of the day was seeing the crowds overwhelm the streets. “It’s just precious,” said Sonum Saeed, 22, “to see these people come together for a little boy’s dream.” Brian Barry, a young FedEx worker, held a sign that said “From 1 Batman Fan 2 Another, I Believe in You” and wore a Batman cap. “I’m happy everything like this happened for him,” he said. “He’s my hero now.”

After Batkid finished saving Gotham City, the crowds flocked to City Hall for a ceremony in his honor. Mayor Edwin Lee gave Miles a key to the city. The local FBI branch deputized him as an honorary junior special agent. The District Attorney announced charges against the Riddler and Penguin. And Patricia Wilson, head of the Bay Area’s Make-A-Wish Foundation, gave everyone some good news. “Miles finished his chemotherapy in June,” she said to cheers. “Ladies and gentlemen, our superhero is in remission and today, I think we gave him a little of his childhood back.”

City leaders proclaimed Nov. 15 as Batkid Day and gave Miles a framed copy of the next day’s Gotham City Chronicle, a special edition put out by the San Francisco Chronicle. Wilson gave a shout out to President Obama, who had sent a tweet congratulating Batkid on rescuing the City by the Bay from certain doom. Police Chief Greg Suhr, who appeared choked up, gave locals a shout out, too. “This is off the hook, San Francisco,” he said.

Miles did not make any remarks, but he smiled and threw up crowd-pleasing fist bumps as every imaginable official heaped praise upon him. His family, including his little brother — dressed as Robin, of course — beamed as the crowd broke out in chants of “Let’s go, Batkid!” Toward the end of the ceremony, Miles’ father Nick Scott took the microphone. The representative from Make-A-Wish asked him what this day meant to him.